home *** CD-ROM | disk | FTP | other *** search
- DOCUMENT:Q103144 04-NOV-1993 [W_NT]
- TITLE :ZEOS 486/50 with More Than 16 MB RAM May Generate Kernel Trap
- PRODUCT :Windows NT
- PROD/VER:3.10
- OPER/SYS:WINDOWS
- KEYWORDS:
-
- ----------------------------------------------------------------------
- The information in this article applies to:
-
- - Microsoft Windows NT operating system version 3.1
- - Microsoft Windows NT Advanced Server version 3.1
- ----------------------------------------------------------------------
-
-
- SYMPTOMS
- ========
-
- ZEOS 486/50 machines with greater than 16 megabytes (MB) of RAM may
- give Windows NT a kernel trap if the SRAM option is enabled in the
- system CMOS.
-
- CAUSE
- =====
-
- The ZEOS 486/50 has an optional SRAM cache that may be enabled. If
- this setting is enabled on machines that have more than 16 MB of
- physical RAM installed, the machine may exhibit a kernel trap when you
- boot the system.
-
- RESOLUTION
- ==========
-
- To correct this problem, either disable the SRAM Cache option in the
- CMOS settings if more than 16 MB of RAM is to be installed, or install
- 16 MB or less of physical RAM and enable the SRAM Cache option.
-
- MORE INFORMATION
- ================
-
- For more information regarding machines with memory greater than 16
- MB, refer to the README.WRI file in the \<wnt root>\winnt\system32
- directory.
-
- The following is an excerpt from README.WRI:
-
- When accessing memory above 16 MB, Windows NT Virtual Direct Memory
- Access compensates for the limitations inherent in the 24-bit DMA
- hardware used by 16-bit ISA bus PCs using a technique called double
- buffering.
-
- Double buffering usually provides performance that is within a few
- percent of 32-bit hardware DMA used with 32-bit bus architectures
- (such as EISA, MCA, etc). In general, Windows NT will continue to take
- full advantage of additional RAM in PCs with ISA, EISA, MCA, and other
- 32-bit bus architectures up to a maximum of 4 GB.
-
- A few ISA-based PCs have unusually poor hardware secondary cache
- schemes. On these machines, increasing memory beyond 16 MB will
- actually degrade, rather than improve, performance. This is a hardware
- limitation of these particular machines and is not specific to Windows
- NT.
-
- Additional reference words: 3.10 trap memory kernel
- KBCategory:
- KBSubCategory: hrdwr
-
- =============================================================================
-
- THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS
- PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS
- ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES
- OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO
- EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR
- ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL,
- CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF
- MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE
- POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION
- OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES
- SO THE FOREGOING LIMITATION MAY NOT APPLY.
-
- Copyright Microsoft Corporation 1993.